Effects of bone morphogenetic protein-2 on aggrecan and collagen type II in rabbit lumbar intervertebral disc cells

Objective:To study the effects of bone morphogenetic protein-2 (BMP-2) on aggrecan and collagen type Ⅱ in the intervertebral disc cells of New Zealand white rabbits in vitro. Methods:The intervertebral disc cells were isolated from the nucleus pulpous of lumbar intervertebral discs of New Zealand white rabbits. The cells were treated with 0 (group A,control group),10 (group B),100 (group C),and 1 000 (group D) ng/ml of BMP-2 in vitro. The cell supernatant was collected after 3 and 6 days. The expressions of proteoglycan and collagen were determined by Antonopulos method and Miamine method,respectively. The expressions of aggrecan and collagen type Ⅱ mRNA were detected by reverse transcription polymerase chain reaction (RT-PCR). Results:The expressions of proteoglycan and collagen gradually increased after treated with different doses of BMP-2 in a dose-dependent manner. The expressions of aggrecan and collagen type Ⅱ mRNA in groups B,C,and D were higher than those in control group. Conclusion:BMP-2 could increase the expressions of collagen and proteoglycan,and thus it may play an important role in the repair of the degenerative intervertebral disc.